Biology - Ecology and the Environment

iGCSE Biology - Ecology and the Environment

Consumer

An organism that eats other organisms

Producer

An organism that can make its own food.

Primary Consumer

An organism that feeds on producers.

Secondary Consumer

An organism that eats primary consumers

Tertiary Consumer

An organism that eats secondary consumers

Predator

An animal that hunts other animals for food

Prey

Animal hunted or caught for food

Carnivore

An animal that eats other animals

Herbivore

An animal that eats only plants

Omnivore

An animal that eats both plants and animals

Decomposer

An organism that breaks down wastes and dead organisms, helps to recycle nutrients.

Food Chain

A series of steps in which organisms transfer energy by eating and being eaten

Food Web

A community of organisms where there are several interrelated food chains

Pyramid of Number

Representation of the number of individual organisms in each trophic level of an ecosystem

Pyramid of Biomass

A pyramid that illustrates the total mass of all the organisms in a trophic level.

Biomass

A measure of the total dry mass of organisms within a particular region.

Trophic Level

Each step in a food chain or food web

Quadrat

A square used to measure and estimate population number and changes between different areas

Decay

A breaking down or rotting.

Carbon Cycle

Movement of carbon in different chemical forms from the environment to organisms and then back to the environment.

Combustion

Anything that is burned

Respiration

Conversion of energy stored in glucose molecules into energy the cells can use

Photosynthesis

Plants using the sun's energy to convert water and carbon dioxide into sugars

Pollutant

A material found in air, water, or soil that is harmful to humans or other organisms

Global Warming

An increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes)

Greenhouse Gas

Gases such as carbon dioxide, methane, nitrous oxide, water vapor, and ozone in the atmosphere which are involved in the greenhouse effect.

Greenhouse Effect

Process by which atmospheric gases trap heat close to Earth's surface and prevent it from escaping into space

Deforestation

Destruction or loss of forests

Eutrophication

pollution of water by fertiliser leading to excessive growth of algae on the surface preventing light from reaching the underwater plants

Habitat

Place where an organism lives

Population

All organisms of a particular species found in an ecosystem at a certain time.

Ecosystem

A self-supporting system of organisms interacting with each other and with their physical environment.

Community

The populations of all species found in an ecosystem at a particular time.

Species

A group of similar organisms that can breed and produce fertile offspring.

Leaching

Removal of dissolved materials from soil by water moving downwards

Soil Erosion

the washing away of soil by the flow of water

Fertiliser

any substance such as manure or a mixture of nitrates used to make soil more fertile

Pesticide

A chemical intended to kill insects and other organisms that damage crops.

Radiation

Heat transferred from one object through space/atmosphere to another object

Biotic factor

the living factors in an organism's environment

Abiotic factors

Non-living components of environment.

Biological pest control

The use of certain organisms by humans to eliminate or control pests. e.g. ladybirds to eat aphids